Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Neuroendocrine regulation of osmoregulation and the evolution of air-breathing in decapod crustaceans
Autore:
Morris, S;
Indirizzi:
Univ Bristol, Sch Biol Sci, Morlab, Bristol BS8 1UG, Avon, England Univ Bristol Bristol Avon England BS8 1UG Bristol BS8 1UG, Avon, England
Titolo Testata:
JOURNAL OF EXPERIMENTAL BIOLOGY
fascicolo: 5, volume: 204, anno: 2001,
pagine: 979 - 989
SICI:
0022-0949(200103)204:5<979:NROOAT>2.0.ZU;2-E
Fonte:
ISI
Lingua:
ENG
Soggetto:
CRAB ERIOCHEIR-SINENSIS; PURPLE SHORE CRAB; ACID-BASE-BALANCE; BIRGUS-LATRO L; CRAYFISH PACIFASTACUS-LENIUSCULUS; EPITHELIAL POTENTIAL DIFFERENCE; ISOLATED PERFUSED GILLS; HEMIGRAPSUS-NUDUS DANA; NA+/K+-ATPASE ACTIVITY; CARCINUS-MAENAS L;
Keywords:
land crab; ion regulation; air-breathing; monoamine; osmoregulation;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Agriculture,Biology & Environmental Sciences
Life Sciences
Citazioni:
75
Recensione:
Indirizzi per estratti:
Indirizzo: Morris, S Univ Bristol, Sch Biol Sci, Morlab, Bristol BS8 1UG, Avon, England Univ Bristol Bristol Avon England BS8 1UG S8 1UG, Avon, England
Citazione:
S. Morris, "Neuroendocrine regulation of osmoregulation and the evolution of air-breathing in decapod crustaceans", J EXP BIOL, 204(5), 2001, pp. 979-989

Abstract

Gills are the primary organ for salt transport, but in land crabs they areremoved from water and thus ion exchanges, as well as CO2 and ammonia excretion, are compromised. Urinary salt loss is minimised in land crabs by redirecting the urine across the gills where salt reabsorption occurs, Euryhaline marine crabs utilise apical membrane branchial Na+/H+ and Cl-/HCO3- exchange powered by a basal membrane Na+/K+-ATPase, but in freshwater crustaceans an apical V-ATPase provides for electrogenic uptake of Cl- in exchange for HCO3-. The HCO3- is provided by carbonic anhydrase facilitating CO2 excretion while NH4+ can substitute for K+ in the basal ATPase and for H+ in the apical exchange. Gecarcinid land crabs and the terrestrial anomuran Birgus latro can lower the NaCl concentration of the urine to 5% of that of thehaemolymph as it passes across the gills. This provides a filtration-reabsorption system analogous to the vertebrate kidney. Crabs exercise hormonal control over branchial transport processes. Aquatic hyper-regulators release neuroamines from the pericardial organs, including dopamine and 5-hydroxytryptamine (5-HT), which via a cAMP-mediated phosphorylation stimulate Na+/K+-ATPase activity and NaCl uptake, Freshwater species utilise a V-ATPase, and additional mechanisms of control have been suggested. Crustacean hyperglycaemic hormone (CHH) has now also been confirmedto have effects on hydromineral regulation, and a putative role for neuropeptides in salt and water balance suggests that current models for salt regulation are probably incomplete. In a terrestrial crabs there may be controls on both active uptake and diffusive loss. The land crab Gecarcoidea natalis drinking saline water for 3 weeks reduced net branchial Na+ uptake but not Na+/K+-ATPase activity, thusimplying a reduction in diffusive Na+ loss. Further, in G. natalis Na+ uptake and Na+/K+-ATPase were stimulated by 5-HT independently of cAMP, Conversely, in the anomuran B. latro, branchial Na+ and Cl- uptake and Na+/K+-ATPase are inhibited by dopamine, mediated by cAMP, There has been a multiple evolution of a kidney-type system in terrestrial crabs capable of managing salt, CO2 and NH3 movements.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 30/11/20 alle ore 11:34:55